Weighty Water

Imagine a plastic cup floating vertically in a bathtub. If empty, the cup would fall to one side, fill with bathwater, and sink. The same, unfortunately, is true for an empty cargo ship. This is why ships take on water as ballast when they leave a port with less-than-full cargo.

To the chagrin of environmental managers, this “ballast water” can contain pollutants, aquatic organisms, and microbes from the port of origin. When the ship enters a new port and takes on more cargo, it jettisons the ballast water, along with its biological stowaways. These organisms can become invasive, and can wreak havoc on ecosystems.

One of the most widely known aquatic invaders is the zebra mussel, which was introduced to the Great Lakes by ballast water. Because invasive species originate in one location and invade another, they often cause problems for the local ecosystem by using resources and space that native species need, eating native species, or both. Invasive species disrupt both ecosystems and economies, with the annual cost of invasions in the US estimated at over $120 billion a year.

The US Environmental Protection Agency (EPA) is one of the primary institutions charged with regulating ballast water, as authorized by the Clean Water Act. But not everyone thinks the EPA is doing the best it can.

In early October 2015, the Second Circuit Court of Appeals released its opinion in the case of Natural Resources Defense Council et al. vs. United States Environmental Protection Agency, in which four environmental organizations challenged the EPA’s regulation of ballast water. The Court’s decision pivoted on the fact that the EPA has been setting standards for ballast water without proper consideration of existing technological capabilities. The Clean Water Act requires the EPA to set pollution standards at the most stringent achievable with today’s technology. This is known as a “technology-based standard.” A more complete legal discussion of the case can be found here.

When setting ballast water standards, the EPA consulted two panels of scientific experts: the EPA Science Advisory Board, and the National Academy of Science Committee on Assessing Numeric Limits for Living Organisms in Ballast Water. These experts were meant to advise the EPA on the usefulness of different levels of standards in mitigating species invasions and also outline technologies available to ballast water treatment. However, scientists are still uncertain why some species successfully invade and others fail to establish themselves in new ports. The only fail-proof way to avoid invasion is to completely eliminate risk by allowing no species in ballast water, but that is currently impossible to guarantee with today’s technologies.

The EPA standards challenged in the court case were designed to match regulations set by the International Maritime Organization. The court found that these limits fall short of the highest level of protection achievable using today’s technology, a requirement of technology-based regulation as outlined in the Clean Water Act.

Now, the EPA must go back to the drawing board.

According to the Court, “technology-based effluent limits (TBELs) set effluent limitations based on how effectively technology can reduce the pollutant being discharged.” Furthermore, “Congress designed this standard to be technology-forcing, meaning it should force agencies and permit applications to adopt technologies that achieve the greatest reduction in pollution.”

The Court’s definition of “technology forcing” differs slightly but significantly from other interpretations of the term. For example, according to experts in the field, technology forcing is “a strategy where a regulator specifies a standard that cannot be met with existing technology, or at least not at an acceptable cost.” Technology-forcing regulations spur investment in R&D, and better technologies are developed to meet the standards. This is different than technology-based regulations, which require implementation of the best existing standard. At best, technology-based regulation could lead to innovations that decrease cost and in doing so improve the technology. But the limits are still set at today’s capabilities.

One iconic example of effective technology forcing is the development and application of the catalytic converter and three-way catalyst in cars in response to the Clean Air Act. By the time the Clean Air Act was passed in the 1960s, air pollution was causing a public health crisis primarily due to automobile emissions. In 1970 the Clean Air Act Amendments were passed into law, calling for extreme cuts in the emissions of hydrocarbons, carbon monoxide, and NOx. The mandated emission standards were well beyond what was possible with existing automobile technologies at that time. There is an intricate backstory to the development of the catalytic converter and the three-way catalyst but it is clear that both technologies enabled immense decreases in automobile emissions and both were products of technology forcing.

It is important to clearly differentiate technology-based standards from technology forcing because the two lead to different endpoints: one in which environmental managers are restricted by existing technologies, and the other in which our environmental needs lead to technological innovation. Given its previous successes, technology forcing should be considered as a policy tool for addressing the spread of invasive species in ballast water.

Even after the EPA returns to the drawing board and proposes new ballast water standards, can we expect aquatic species invasions to decrease if those standards are limited by today’s technologies? Or is the rigor provided by true technology forcing our best hope to ameliorate the invasion crisis? Unfortunately we may never know if the new EPA standards are locked in at today’s technological ceiling.

Featured Photo Caption: “The Port of Seattle accepted just under 500 vessel calls from cargo ships in 2014, representing almost 500 opportunities for invasive species to hitchhike their way into the waters of Puget Sound. (Photo credit: Ellie Bors)”

Ellie Bors is a PhD candidate in the MIT - Woods Hole Oceanographic Institution Joint Program in Oceanography. She currently studies the evolutionary genetics of marine animals, with a specific focus on invasive marine species. She is also pursuing a certificate in Science, Technology, and Policy from MIT, and is broadly interested in marine resource and biodiversity management. Outside the lab, Ellie enjoys playing her cello, known affectionately as Zoltan.